Jun 9, 2011

Freedom & Ubuntu

Writers: Matthew Helmke,
 Andrew Hudson, Paul Hudson
Language: English
Paperback: 769 pages
Data: March 15, 2011

Jun 8, 2011

PuTTY Config!

PuTTY is a free and open source terminal emulator application which can act as a client for the SSH, Telnet, logging, and raw TCP computing protocols and as a serial console client. The name "PuTTY" has no definitive meaning, though 'tty' is the name for a terminal in the Unix tradition, usually held to be short for teletype.

PuTTY was originally written for Microsoft Windows, but it has been ported to various other operating systems. Official ports are available for some Unix-like platforms, with work-in-progress ports to Classic Mac OS and Mac OS X, and unofficial ports have been contributed to platforms such as Symbian and Windows Mobile.

PuTTY Vs. Telnet?  PuTTY win! download

PuTTY  |ـــــ Serial  |ـــــ Enter  |ـــــ en or enable  |ـــــ conf t  |ـــــ line con or line console 0 
router name# show interface status
address  |ـــــ add

May 28, 2011

ARP (Address Resolution Protocol)

It help ip network devices find other device on the same segment or Vlan |ـــــ ARP uses a local broad cast to discover neighboring device |ـــــ ARP resolves ip addresses to mac addresses so that machines on the same data link layer media can communicate with each other.

Protocol                                                                                   Protocol ID
Internet Control Message Protocol (ICMP)                                          1
Transmission Control Protocol (TCP)                                                  6
Interior Gateway Routing Protocol (IGRP)                                          9
User Datagram Protocol (UDP)                                                           17
Internet Protocol version 6 (IPv6)                                                       41
Internet-work Packet Exchange (IPX)                                                    111

Internet Control Message Protocol (ICMP)

  • It is used to send error & control information between ip network devices.
  • There are many diffident messages that can be shared, including the following: 
1. Echo request: Determines whether on ip node ( a host or a router is available on network.)
2. Echo Reply: Replies to ICMP echo request.
3. Destination Unreachable: Informs the host that a datagram can't be delivered.
4. Source Quench: Informs the host to lower the rate at which it sends datagram because of congestion.
5. Redirect: Informs the host of a preferred rate.
6. Time Exceeded: Indicate that the TTL of IP datagram has expired.

May 21, 2011

What is Datagram?

A datagram is a basic transfer unit associated with a packet-switched network in which the delivery arrival time and order are not guaranteed. A datagram consists of header and data areas, where the header contains information sufficient for routing from the originating equipment to the destination without relying on prior exchanges between the equipment and the network. The source and destination addresses as well as a type field are found in the header of a datagram.